The present invention relates to a device for optically monitoring or detecting information regarding a moving object and, more particularly, to a device using optical fibers for optically monitoring or detecting information regarding a moving object.
In the optical type device for monitoring a moving object disclosed in Japanese Patent Laid-Open No. 60-159656 and 62-67409, a holder affixed to an end of an optical fiber is directly installed on the wall of a container for holding a moving object to be monitored.
The above conventional optical fiber type device for monitoring a moving object does not take into consideration the environment in which it is used. "The installation posture" of the holder changes with the passage of time because of heat and vibration from the container for holding the holder. As a result, the distance between the device and a moving object to be monitored, and the position in which the device is installed, shift. This leads to a problem in that it is impossible to obtain an accurate light signal output.
Such a problem becomes pronounced especially when the device is utilized near an internal combustion engine or a turbine.